Undercut-saw guide.



J. W. PETTIJOHN. .UNDEROUT SAW GUIDE. APPLICATION FILED FEB. 20, 1907.

Patented Sept. 15, 1908.

JOHN WILSON PETTIJOHN, OF MNTESANO, WASHINGTON.

UnDEno-U'r-sAw GUIDE.

Specification of Letters Patent.

Patented Sept. '15, 1908.

Application filed February 20, 1907. Serial No. 353,368.

,To all whom "it may Wncem:

, guides, and to increase the strength and durability of thesarne andlessen the weight thereof, and; to. enable undercut saw guides to beconstructed'more cheaply and easily than heretofore. V

A further object of the invention is to, pro vide undercut saw guides,adapted to afford a support for a crosscut saw, and capable of beingreadily driven into and removed from a log without injury to the guide.

Another object of the invention is to provide an undercut saw guide,which may be adjusted more'rapidly than heretofore, and which when notin use, maybe compactly fold ed so as to be conveniently carried in thepocket from one placeto another-r i/Vith these and other objects inview, the invention consists in the" construction and novel combinationof parts hereinafter fully described, illustrated in the accompanyingtrated in dotted lines.

tive view of the saw guide detached.

stantially on the line ra: of Fig. 1.

drawing, and pointed out in the claims hereto appended; it beingunderstood that vari ous changes in the form, proportion, size and minordetails of construction, 'within the scope of the claims, may beresorted to without departing from the spirit or sacrificing any of theadvantages of theinvention.

'In the drawing :Figure 1 is a side elevation of an undercut saw guide,constructed in accordance with this invention, and shown applied to alog, the saw being illus- Fig. 2 is a pers ec- 1g. is a transversesectional view, taken sub- Fig. 4 is a detail sectional view,illustrating /the construction of the saw sup orting wheel and themanner of mounting tl ie same.

Like numerals of reference designate corresponding parts in all thefigures of the draw- 1ng.

1 designates a dog, provided at'the top with a curved bill 2, tapered toa point and adapted to be driven into the side of a log 3, and the billpresents a lower concave face to the log, whereby the dog wilhbe firmlyheld engagement with the log by the downward strain resulting from theuse of a crosscut saw. The dog 1 is provided with an approximatelysigmoidally curved shank 4, presenting a forwardly projecting convexface 5 to the log, whereby the dog is firmly supported in position onthe log. ThGgflOIlt or inrier convex face 5 is located" at a pointbetween the ends of the shank or body of the dog, and the upper portionof the shank curves outwardly from the log to provide a loop or open ing6, adjacent tomthe bill to enable a crow bar,'or other tool to bereadilyintroduced between the shank or body of the dog and the log for pryingthe bill out of the same. This will enable the dog to be easily-andquickly removed from a log without injury to the former.

' The lower portion of the shank or body of the dog is curved outwardlyor. rearwardly'from the log, and the'metal is bent backward on the shankor body and is extended to form,

a reinforcing .or bracing portion 7.; The doubling or bending of themetal to provide the reinforcing or bracing portion 7, forms an eye 8for'the reception of a bolt 9. The

'eye 8 is. counter-sunk at one side to form a seat for a cup-shaped orconical clamping member or washer 10, which receives the inner portionof the head 11 of the bolt 9. The threaded portion of the bolt receivesa nut 12, which is rovided with a suitable crank arm or hanr le 13,'butany other .suitable means may be employed for turning the nut. v

, The head'll of the bolt is provided with a rectangular opening 14,through which an ad; .justable hanger bar 15 passes.

bar is rectangular in cross section to conform.

' to the configuration of the square opening of the head of-the bolt,and it is curved or bowed lon itudinally"tofrictionally' engage thewalls 0 the bolt opening, whereby when the nut'is loosened, the hangerbar will be proventedv from drop ing in the opening 14. The u per end 16oi the hanger bar is reduced and t readed to receive a nut 17 whichforms a sto' I movement of the hanger bar to prevent the samefromacoidentally leaving the opening of the bolt, and the latterconstitutes a pivotfor The hanger for limiting the downward I vshaft ors indle 18, also have an annular for enabling the same to be ried in thepocket.

9 cup-shaped washer is forced into engagementposed of disks 23 and 24,secured to ether by ject beyond the peripheries of the latter and and atthe same time possesses great strength. Also it will be clear that, asthe curved the hanger bar to permit the latter to be folded' alongsidethe dog to shorten the device conveniently car- The hanger bar is secured in its adjustment by means of the cupshaped or conical washer,which projects beyond the inner edge of the head of the bolt,andjengages the hanger bar aboveand below the same. The inner corners ofthe head of the bolt are beveled to provide an inner tapering portion tofit within the conical or cup-shaped washer, but the head of the boltmay be of any other preferred configuration. When the nut 12 istightened, the conical or with the adjacent side or face of the curvedhanger bar, and this together with the frictional engagement of thehanger bar and the eye of the bolt, firmly holds the hanger bar in itsadjusted position.

The lower end of the hanger bar is provided with a transverse shaft orspindle 18, formed integral with the hanger bar and receiving a saw sugaporting wheel 19, secured on the shaft or spin e by a nut 20. The nut20 engages the outer end of the shaft or spindle, whlch is threaded, andthe washer 21 is preferably interposed between the nut and the sawsupportin and guiding wheel 19. Any other suitab e means, however, maybeemployed forretaining the wheel-on the shaft or spindle of the hangerbar. The saw supportin wheel, which is provided with a plurality osaw-receiving grooves 22, is preferably comtransverse rivets 25, orother suitab e fastening devices. The disks 23, which are of greaterdiameter than the other disks 24, proorm the side walls of the grooves22. The disks, which are provided with registering central, openings toreceive the transverse series of ahned eccentrically arranged openingsspaced from the central openings and receivin fastenin devices 25, whichare arrange( outside 0 the shaft or spindle 18.v The inner side disk isprovided with an intcgral projecting hub extension, which spaces the sawsupporting wheel from the hanger bar.

It will be seen that a: t shank or body of the dog is bent back uponitself to rovide the reinforcing portion and to form the eye, it may. beeasily and cheaply manufactured,

hanger bar frictionally engages the 'walls of the bolt opening, and isthereby prevented from dropping through the same, when the nut of thebolt is loosened, the device may be more easily and quickly adjustedthan one having a straight bar or slot.

Havingthus fully described my invention, l

what I claim as new and desire to secure by 2. An undercut saw guideprovided with a dog consisting ofa bill, and a substantially sigmoidallycurved body. extending downwardly from the bill andforming anintermediate forwardly projecting log-engaging portion, providing anupper loop or opening ocated adjacent to the bill to permit theintroduction of a tool for withdrawing the bill from a log.

3. An undercut saw guide comprising a dog consisting of a body providedat one end with a bill, and having its other end bent upon itself toform an eye and extending beyond the eye to provide a reinforcingportion, a saw supporting hanger, and fastening means passing throughthe eye of the dog for securing the hanger to the latter.

4. An undercut saw guide com rising a dog provided with an enlarged eyeaving a tapered opening at one side forming a conical seat, a fasteningbolt'extending through the opening of the dog and provided with anintegral e e, a hanger bar passing through the eye oft e bolt andprovided at its lower portion with saw supporting means, a conicalclamping washer fitted partially within the said seat and bearingagainst the inner edge of the eye of the bolt and also against the innerside face of the hanger bar, and a nut mounted on the fastening bolt foradjusting the parts toclamp the hanger bar.

5. An undercut saw guide comprising a Fog having one end doubled back onitself and forming an enlarged eye, the latter being ta ered to rovide aconical seat, a fastening bo t exten ing through the eye of the dog andhaving an integral eye beveled at the inner side, a curved hanger barassing through the eye of the bolt and provided at its inner side with aflat face, a conical clamping washer fitted partially within the saidseatand bearing against the flat face of the hanger bar, a nut mountedon the bolt for adjusting the parts to clamp the hanger bar, and sawsupporting means carried by he hanger bar.

In testimony, that I claim the foregoing as my own, I have heretoaffixed my signature in the presence of two witnesses.

JOHN WILSON PETTIJOHN. Witnesses:

' ERNEST MARION FRnNcn,

JACOB L; PHILLIPS.

